• 치과방사선
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• 제22권2호
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• pp.367-373
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• 1992

저자들은 양측 하악체부위의 종창을 주소로 경북대학교병원 치과에 내원한 35세 남자에서 임상ㆍ방사선학적 검사와 조직병리학적 검사를 통해 양측성 백악질섬유종을 진단하고 아래와 같은 사항을 관찰하였다. 1. 임상적으로 하악체 양측부위의 점진적 종창으로 인한 안모변형이 관찰되었다. 2. 방사선학적으로 양측 하악체부위에 각각 방사선불투과성 괴를 가진 방사선투과성의 병소가 관찰되었으며, 협설측 피질골의 비박, 팽윤과 병소에 인접한 치아들의 치조백선 소실과 치근 흡수가 관찰되었다. 3.조직병리학적으로 섬유아세포 및 백악질아 세포들이 조밀하게 분포된 결체조직으로 구성되었고 내부에 원형 또는 난원형의 호염기성의 백악질양 괴가 다수 산재하였다.

• Applied Microscopy
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• 제31권4호
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• pp.325-331
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• 2001

돌가자미의 피부 상피층을 다층상피층으로 지지세포, 선세포 그리고 과립세포들로 구성된다. 상피층은 지지세포의 형태와 구조에 따라 표면층, 중간층 및 기저층으로 구분 할 수 있었다. 지지세포들의 세포질은 피질부와 수질부로 나누어지는데 피질부에는 미세섬유의 발달이 뚜렷하다. 점액세포들은 단세포선으로 상피의 표면층과 중간층에서 관찰된다. 점액세포의 점액물질은 중성이며, carboxylated mucosubstance의 당단백 질로 확인되었다. 곤봉상세포는 세포질에 잘 발달된 활면소포체와 골지체를 가진다. 과립세포는 주로 중간층과 기저층에 존재하고, 세포질은 막을 가진 전자밀도가 높은 과립들이 차지한다. 색소세포는 세포질에 존재하는 함유물의 전자밀도에 따라 세 종류로 구분할 수 있었으며, 색소세포 근처에서 신경종말을 관찰할 수 있었다.

• 치과방사선
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• 제27권1호
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• pp.217-230
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• 1997

The location of the mandibular canal and the cortical thickness of the mandible is important in the practice of dentistry. This study was performed on twenty chosen dry mandibles, which were of adults and included fully erupted premolars and molars. The purpose of this study was to evaluate the location of the mandibular canal and the cortical thickness of the mandible on computed tomograms and to aid in the surgical treatment plans. The obtained results were as follows; 1. The horizontal distance between the mandibular canal and the buccal external border was 6.6±0.9mm on Somesial root of the first molar), and it was increased posteriorly. The horiwntal distance between the mandibular canal and the lingual external border was 4.1±1.lmm on S/sub 0/, and it was decreased posteriorly. 2. The vertical distance between the alveolar crest and the mandibular canal was 16.9±1.6mm on S/sub 0/, and it was decreased posteriorly. The vertical distance between the inferior border of mandible and the mandibular canal was 8.8±1.3mm on S/sub 0/, and it was increased anteriorly and posteriorly. 3. The thickness of the buccal cortical plate was 2.2±0.4mm on S/sub 0/. and it was increased posteriorly. But, that of the lingual cortical plate was 2.0±0.6mm on S/sub 0/ and it was decreased posteriorly. 4. The area of the buccal cortical plate was 66.5±1.0mm² on S/sub 0/. and it was increased posteriorly. But, that of the lingual cortical plate was 65.8±0.9mm² on S/sub 0/ and it was decreased posteriorly.

• 대한치과보철학회지
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• 제37권5호
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• pp.607-619
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• 1999

Cortical support is an important factor, as the engagement of the fixture in strong compact bone offers an increased load-carrying capacity and initial stability. Because of the poor bone quality in the posterior mandible and other anatomic considerations, it has been suggested that implant fixtures be placed in these locations with apical engagement of the lingual cortical plate for so-called bicortication. The purpose of this investigation was to determine the effect of cortical engagements and in addition polyoxymethylene(POM) intramobile connector(IMC) of IMZ implant on implant load transfer in edentulous posterior segment of mandible, using three-dimensional (3D) finite element analysis models composed of cortical and trabecular bone involving single implant. Variables such as (1) the crestal peri-implant defect, (2) the apical engagement of lingual cortical plate, (3) the occlusal contact position (a vertical load at central fossa or buccal cusp tip), and (4) POM IMC were investigated. Stress patterns were compared and interfacial stresses along the bone-implant interface were monitored specially. Within the scope of this study, the following observations were made. 1) Offset load and angulation of fixture led to increase the local interfacial stresses. 2) Stresses were concentrated toward the cortical bones, but the crestal peri-implant defect increased the interfacial stresses in trabecular bone. 3) For the model with bicortication, it was noticed that the crestal cortical bone provided more resistance to the bending moment and the lingual cortical plate provided more support for the vertical load. But Angulation problem of the fixture from the lingual cortical engagement caused the local interfacial stress concentrations. 4) It was not clear that POM IMC had the effect on stress distribution under the present experimental conditions, especially for the cases of crestal peri-implant defect.

• Imaging Science in Dentistry
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• 제32권2호
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• pp.81-87
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• 2002

Purpose : To investigate the diagnostic significance of cortical changes in the bone of diseased jaws utilizing computed tomography (CT). Materials and Methods: Computed tomographic images of 91 patients, consisting of 7 osteomyelitis, 46 cysts, 18 benign tumors, and 20 malignant tumors, were analyzed. The pattern of cortical expansion was classified into three types: no expansion (N), buccal or lingual expansion (B/L), and buccolingual expansion (B & L). The pattern of cortical destruction was classified into four types: no destruction (N), point destruction (PO), gross destruction (GR), and permeative destruction (PE). The pattern of periosteal reaction was classified into four types: parallel, irregular, spicule, and Codmans triangle. The relationship between the pattern of cortical bone changes and diseases of the jaws was assessed. Results: When the pattern of cortical expansion was compared to diseases of the jaw, N-type was most prevalent in cases of osteomyelitis and malignant tumors, B/L-type with cysts, and B&L-types with benign tumors. Comparison between the pattern of cortical bone destruction with diseases of the jaw showed strong correlations between PO and PE-types to osteomyelitis, N-type with cysts, N and GR-types with benign tumors, and GR-type with malignant tumors. Finally, the relationship between the pattern of periosteal reaction to diseases of the jaw showed a strong correlation between parallel-type to osteomyelitis and spicule-type to malignant tumors. Conclusion : The pattern of cortical expansion and cortical destruction is useful in differentiating diseases of the jaws.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제28권4호
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• pp.249-255
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• 2002

Recently, Skeletal Anchorage System (SAS) has been focused clinically with the view point that it could provide the absolute intraoral anchorage. First, it began to be used for the patient of orthognathic surgery who had difficulty in taking intermaxillary fixation due to multiple loss of teeth. And then, its uses have been extended to many cases, the control of bone segments after orthognathic surgery, stable anchorage in orthodontic treatment, and anchorage for temporary prosthesis and so on. SAS has been developed as dental implants technique has been developed and also called in several names; mini-screw anchorage, micro-screw anchorage, mini-implant anchorage, micro-implant anchorage (MIA), and orthosystem implant etc. Now many clinicians use SAS, but the anatomical knowledges for the installed depth of intraosseous screws are totally dependent on general experiences. So we try to study for the cortical thickness of maxilla and mandible in Korean adults without any pathologic conditions with the use of Computed Tomography at the representative sites for the screw installation.

• 치과방사선
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• 제28권2호
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• pp.355-362
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• 1998

법랑모세포종은 흔히 중년에 호발하는 질환으로 알려져 있지만 아동 및 청소년에서도 그 발생이 보고되고 있다. 그러나 어린 환자들에 발생한 법랑모세포종의 임상적, 방사선학적 및 조직학적 분석은 드물다. 본 연구는 1984년 8월에서 1998년 5월 사이에 부산대학교병원에서 법랑모세포종으로 진단받은 46명의 환자들중에서 18세 이하 환자 15명에 대한 후향적연구로서 아동 및 청소년에서의 법랑모세포종의 특징을 기술하고자하였다. 그 결과는 다음과 같다. 1. 46례의 법랑모세포종중에서 15(32.6％)례가 18세 이하의 아동에서 발생하였으며, 남자 9(60％)명, 여자 6(40％)명으로 1.5: 1의 남녀비를 나타내었다. 2. 15례 모두 하악에 발생하였으며, 이 중 11(66.7％)례가 대구치부와 하악지에 나타났다. 3. 15례 모두 하악 종창의 주소를 보였다. 4. 방사선학적으로, 11(73.3％)례는 단방성 병소를, 4(27.7％)례는 다방성 병소를 나타내었다. 피질골 종창은 14(93.3％)례에서, 치근흡수는 11(73.3％)례에서 나타났다. 5. 조직학적으로 총상형이 7(46.7％)례, 단낭성형이 6(40％)례, 그리고 여포형이 2(13.3％)례 였다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제29권3호
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• pp.255-261
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• 2007

Preface: Dental implant is important method that may solve the mastication, occlusion, esthetic, temporomandibular joint, and psychologic problem in oral and maxillofacial surgery. It is ideal that all of the implant are well positioned by adequate technique. By the way it‘s not always possible because of some anatomic, physiologic factor. In this case, If the implant can be moved to adequate position, it may be possible more esthetically and implanted patients more satisfied, but the majority of Implantists and orthodontists have thought that it is not possible. However, Implant, in fact, can be moved. and thus we can overcome the limit of implantation more. The aim of the present study was to evaluate the possibility of implant movement after corticotomy. Case report: Patient missed the upper right first molar. and implantation was done after completion of socket healing. We wait six months for osseointegration. Then, corticotomy was done under local anesthesia and close coil was used for orthodontic force. After traction during 3 weeks, we find the change of implant position at horizontal plane. we can not see the degenerative change on adjacent structure and tracted implant. there is a clinical mobility on upper right second premolar that used for anchorage but it subside spontaneously at the timing of prosthetic restoration without additional treatment. Discussion: As we could have some knowledge with this experiment, we report the case of implant movement after corticotomy and suggest a method about more esthetic implant treatment with a review of literature.

• 대한치과보철학회지
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• 제43권1호
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• pp.95-104
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• 2005

Statement of problem. Higher stresses at the cervical bone around dental implants have been seen as a primary cause of the bone resorption at the site. Purpose : To determine the possibility of stress reduction by assembly of different abutment and implant in diameters. Material and methods. Abutments of several different diameters assembled on the top of XiVE$^{(R)}$ implants were axisymmetrically modeled for a series of finite element analyses. Abutments of 3.4, 3.8, 4.5, and 5.5 mm diameters were assumed to be sit on implants of the same or bigger diameters. All the abutments with an exception of 3.4mm dia, are technically possible to be assembled on bigger implants. Main consideration was given to the stresses at the cervical cortical bone induced by loads of parallel to the implant axis. Results and conclusions. 1. Higher stresses were observed at the cervical area of all the models of the same diameters of abutment and future. The peak stresses, which were shown to be a function of the fixture diameter, were from 1-1.85MPa. 2. Difference in the diameters of the abutments and the implants actually reduced the cervical bone stresses. 3. Downsizing of the abutment by one step resulted in 0.1MPa (5%) reduction of the stresses. In light of the relatively lower bone stress, however, this amount of stress reduction was decided to be biomechanically insignificant.

• 대한소아치과학회지
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• 제38권4호
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• pp.421-426
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• 2011

구강내 대부분의 감염은 치성 기원으로 치성 감염은 초기 감염부위로부터 저항이 제일 적은 경로를 따라 확산된다. 상악에서 치근단과 피질골 사이의 두께가 구개측보다 협측에서 더 얇기 때문에 감염이 구개측 보다는 협측으로 더 쉽게 확산되며, 구개 치근보다 협측 치근이 좁아서 근관치료의 실패가 협측 치근에서 많이 발생한다. 따라서 구개 농양의 발생은 협측 농양에 비해 흔치 않다. 구개 농양은 구개부에 발생하는 비치성 기원의 양성 또는 악성 타액선 신생물, 양성 신경 종양, 낭종 등과 감별진단이 어렵다. 따라서 소아에서 구개종창이 관찰될 경우 치성 기원의 구개 농양을 조기에 진단해 감염이 전신적으로 확산되는 것을 방지 해야 한다. 본 증례에서는 유치의 통증과 구개부 종창을 주소로 내원한 환아에서 치성 기원의 구개 농양이라고 진단하여 해당치아를 발치하고 항생제를 처방하였다. 치료 후 구개 종창이 해소되어 보고하는 바이다.